This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A023055 #9 Mar 30 2012 18:35:17 %S A023055 1,2,3,4,5,7,8,9,10,11,12,13,15,16,17,18,19,20,21,23,24,25,26,27,28, %T A023055 30,32,33,35,36,37,38,39,40,41,43,45,47,48,49,51,53,55,56,57,59,60,61, %U A023055 63,65,67,68,69,71,73,74,75,76,77,79,80,81,83,85,87,89,92,93,94,95,97,99,100 %N A023055 (Apparently) differences between adjacent perfect powers (integers of form a^b, a >= 1, b >= 2). %C A023055 Catalan's conjecture (now a theorem) is that 1 occurs just once as a difference, between 8 and 9. %H A023055 Alf van der Poorten, <a href="/A023057/a023057.txt">Remarks on the sequence of 'perfect' powers</a> %Y A023055 Cf. A001597, A023057. %Y A023055 Cf. A189117 (conjectured number of pairs of consecutive perfect powers differing by n). %K A023055 nonn,hard %O A023055 1,2 %A A023055 _David W. Wilson_